Following recent increase in the degree of density and integration of hybrid ICs and printed circuit boards that carry transistors, ICs, memory elements, and other electronic components, various thermally conductive silicone greases, thermally conductive silicone gel compositions, thermally conductive silicone rubber compositions, or the like have been used in order to achieve efficient heat dissipation from such devices.
In order to improve thermal conductivity of the aforementioned conductive silicone compositions by increasing the degree of filling with thermally conductive fillers, it was proposed, as disclosed, e.g., in Japanese Unexamined Patent Application Publication (hereinafter referred to as “Kokai”) 2000-256558, to use a thermally conductive silicone rubber composition comprising an organopolysiloxane, a methylpolysiloxane that contains hydrolyzable groups, a thermally conductive filler, and a curing agent. Furthermore, Kokai 2001-139815 discloses a thermally conductive silicone rubber composition that comprises a curable organopolysiloxane, a curing agent, and a thermally conductive filler, wherein the filler is surface-treated with an oligosiloxane that contains silicon-bonded alkoxy groups.
However, if for improving handleability and workability of such thermally conductive silicone compositions their viscosity is lowered, then after the coated surface assumes vertical position, the coating begins to slip-off.
It is an object of the present invention to provide a thermally conductive silicone composition which possesses excellent handleability and workability at low viscosity and which, after application onto surfaces, is not subject to slipping-off when this surface assumes a vertically position, even under harsh temperature conditions. It is another object to provide an electronic device that employs the aforementioned composition.